Debunk claim:

Recycling already many times debunked myths. Martin Koller, author of all the notorious pro-Kremlin disinformation claims, has been identified as an active informer of the former communist secret police in Czechoslovakia (StB) who believes that the MH17 was not shot down by Russia-backed separatists: http://echo24.cz/a/wtUvk/kdo-nam-vysvetluje-situaci-v-rusku-aktivni-udavac-stb